-LRB- CNN -RRB- -- If you want to see the impact of Iran 's growing power in the Middle East , look no further than Syria .

On Monday , three important developments occurred simultaneously :

First , world diplomats scrambled anxiously to salvage plans for a conference on Syria scheduled to start on Wednesday . The `` Geneva II '' meeting almost went off the rails before it began , with Syrian opposition leaders threatening to stay away unless the United Nations retracted the invitation it had unexpectedly extended to Iran .

At the same time , a new report about the Syrian civil war showed what appears to be convincing evidence of large-scale `` systematic torture and killing '' by the regime of Syrian President Bashar al-Assad , Iran 's top ally . The report 's authors said the new evidence could prove al-Assad and his regime are guilty of perpetrating crimes against humanity .

And in the third major event of that day , the interim nuclear deal between Iran and world powers went into effect . Under the deal negotiated in November , Iran suspended some of its nuclear enrichment operations , and Western governments started lifting some of the economic sanctions they have used to pressure Tehran .

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These three events will be included by historians and analysts when they write the story of the turmoil of the early 21st century Middle East . They will note that this was a week that showed the consequences of Iran 's gradually rising influence , as the Islamic Republic moved steadily toward its goal of becoming the dominant power in the region .

Not long ago , the dictator al-Assad appeared on the verge of losing power to a popular uprising . President Barack Obama declared he `` must get out of the way . '' But his regime 's loyal allies in Tehran sent in reinforcements .

At the urging of its Iranian patrons , Lebanon 's Shiite militia , Hezbollah , moved its forces across the border into Syria , helping to turn the tide of the war and adding to its increasing radicalization . The war went from a grassroots democratic movement to a brutal showdown between Sunni extremists -- whose strongest elements now include al Qaeda fighters -- against Shiite forces loyal to Iran and al-Assad .

Now the Syrian war , which has displaced millions of civilians and has killed more than 130,000 , according to the Syrian Observatory for Human Rights , is spilling into Lebanon , Iraq and elsewhere .

It has become a proxy war for regional rivalries , with Sunni states , including Saudi Arabia and Qatar , supporting the opposition , and Iran , along with Hezbollah , standing steadfastly with al-Assad by providing him with manpower , ammunition and intelligence .

Iran has not only saved al-Assad , it has changed the character of the fight .

It has turned it into a much more dangerous regional conflict , all but eliminating the prospects for a positive outcome anytime soon and adding to the indescribable suffering of the Syrian people .

Where do Iran 's nuclear program and the agreement with world powers fit into all this ?

The interim deal was meant to freeze the nuclear program in place for six months while a final agreement is negotiated . But the announcement of the deal late last year immediately transformed the landscape . In the eyes of Arab states , the U.S. was taking the first steps towards capitulating before Iran 's aspirations . The Iranian regime 's goal is to spread its version of Islamic revolution and to make Iran the most powerful country in the region .

The sight of top American and European diplomats rushing to Geneva to negotiate with Iran sent a strong message . Within days , the balance of power started shifting . Countless delegations crossed the Persian Gulf , as Arab rulers allied with Washington sought to strengthen ties with Tehran . Saudi Arabian officials railed against the United States .

One reason Iran signed the interim deal is that it has already achieved a great deal of what it sought with its nuclear program . Under the so-called Joint Action Plan , Iran has suspended uranium enrichment above 5 % and will start getting rid of its 20 % - enriched uranium , which is close to weapons grade . But nobody thinks the deal , as it stands now , is a solution . In some respects , Iran is already a nuclear power , although it does n't yet have the full immunity that nuclear weapons would create .

As if to reinforce that point , Iran 's top nuclear negotiator , Abbas Araghchi , told Iranian television that if Tehran decided to resume enrichment to its previous levels , it could do it in 24 hours . The White House dismissed the statement as meant for domestic consumption . But the fact is that Iran is not dismantling its centrifuges . It is just unplugging them .

In the meantime , Iran 's economy has already started recovering . European , Asian and Arab businessmen are lining up to make deals with a resurgent Iran . Arab diplomats are speaking in measured tones about their Persian neighbor , but behind the scenes , the worries are palpable .

The mere prospect of an Iranian presence at the Geneva talks came close to scuttling the diplomatic effort . The U.N. withdrew the invitation after the rebels said they would not attend , and both Washington and Riyadh pressured the U.N. . But already Iran and Syria have indicated they have no intention of supporting the meeting 's official goal of creating a transitional government to end Syria 's war . Syria 's regime will likely become more beholden to Iran than ever .

A stronger Iran would deepen the divisions separating Sunnis and Shiites , Arabs and Persians , Saudis and Iranians , Palestinians and Israelis , making them all but impossible to bridge . The region would become a greater threat to itself and the world .

The talks in Switzerland will now start . But the fighting , torture and killing in Syria will continue , even as former war crimes prosecutors say al-Assad is viciously slaughtering his own people .

In the end , much of the Middle East 's future will depend on whether negotiators can find a way to stop Iran from advancing its power to the point where it becomes essentially invulnerable . Otherwise , the region will become an even more dangerous and desperate place , as we see today in Syria .

The opinions expressed in this commentary are solely those of Frida Ghitis

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Frida Ghitis : Syria a good example of Iran 's growing power in the Middle East

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She says Iran is the top backer for al-Assad 's regime , which commits reported atrocities

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She says U.S. wants new Syria government ; Iran 's backing makes al-Assad unlikely to deal

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Ghitis : Interim nuclear deal makes allied Arab nations fear the West will weaken